package com.cskt.shiro;

import com.cskt.common.constants.ErrorCodeEnum;
import com.cskt.common.exception.ServiceException;
import lombok.extern.slf4j.Slf4j;
import org.apache.shiro.util.StringUtils;
import org.apache.shiro.web.filter.authc.BasicHttpAuthenticationFilter;
import org.springframework.http.HttpStatus;
import org.springframework.web.bind.annotation.RequestMethod;

import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

@Slf4j
public class JWTFilter extends BasicHttpAuthenticationFilter {
    @Override
    protected boolean isLoginAttempt(ServletRequest request, ServletResponse
            response) {
        HttpServletRequest req = (HttpServletRequest) request;
        log.info("请求路径为：{}",req.getRequestURI());
//取出cookie中的数据
        Cookie[] cookies = req.getCookies();
        for (int i = 0; i < cookies.length; i++) {
            Cookie cookie = cookies[i];
            if ("token".equals(cookie.getName())) {
//取出cookie中 token对应的值
                String token = cookie.getValue();
                log.info("token:{}",token);
//如果当前token的值不为空则当前用户已登录
                return StringUtils.hasText(token);
            }
        }
        return false;
    }

    @Override
    protected boolean executeLogin(ServletRequest request, ServletResponse
            response) throws Exception {
        HttpServletRequest httpServletRequest = (HttpServletRequest) request;
        //取出cookie中的数据
        Cookie[] cookies = httpServletRequest.getCookies();
        String token = null;
        for (int i = 0; i < cookies.length; i++) {
            Cookie cookie = cookies[i];
            if ("token".equals(cookie.getName())) {
                //取出cookie中 token对应的值
                token = cookie.getValue();
                break;
            }
        }
        log.info("token:{}",token);
        JWTToken jwtToken = new JWTToken(token);
        // 提交给realm进行登入，如果错误他会抛出异常并被捕获
        getSubject(request, response).login(jwtToken);
        // 如果没有抛出异常则代表登入成功，返回true
        return true;
    }

    /**
     *
     * @param request
     * @param response
     * @param mappedValue
     * @return
     */
    @Override
    protected boolean isAccessAllowed(ServletRequest request, ServletResponse response, Object mappedValue){
        if (!isLoginAttempt(request, response)) {
            try {
            //当用户未登录的时候执行登录操作，如果出现异常，则直接抛出异常，
                executeLogin(request, response);
            } catch (Exception e) {
                throw new ServiceException(ErrorCodeEnum.AUTH_NOT_LOGIN);
            }
        }
        return true;
    }

    /**
     * 对跨域的支持
     * @param request
     * @param response
     * @return
     * @throws Exception
     */

    @Override
    protected boolean preHandle(ServletRequest request, ServletResponse
            response) throws Exception{
        HttpServletRequest httpServletRequest = (HttpServletRequest) request;
        HttpServletResponse httpServletResponse = (HttpServletResponse)
                response;
        httpServletResponse.setHeader("Access-control-Allow-Origin",
                httpServletRequest.getHeader("Origin"));
        httpServletResponse.setHeader("Access-Control-Allow-Methods",
                "GET,POST,OPTIONS,PUT,DELETE");
        httpServletResponse.setHeader("Access-Control-Allow-Headers",
                httpServletRequest.getHeader("Access-Control-Request-Headers"));
        // 跨域时会首先发送一个option请求，这里我们给option请求直接返回正常状态
        if (httpServletRequest.getMethod().equals(RequestMethod.OPTIONS.name()))
        {
            httpServletResponse.setStatus(HttpStatus.OK.value());
            return false;
        }
        return super.preHandle(request, response);
    }




}


